Truant youths represent an important target group for addressing drug use and related problems. Effective interventions may reduce their troubled behavior in school and lower their risk for moving into the juvenile justice system. In addition to arrested youths who are processed at the Hillsborough County, Juvenile Assessment Center (JAC), youths are brought to the JAC Truancy Center by law enforcement because they have been truant from school. Relevant research, including information collected on JAC truants, indicates that, compared to youths who regularly attend school, truants often score lower on academic ability and achievement tests, have contact with the juvenile justice system, have family problems, and experience more drug abuse. For example, among 174 truants processed at the JAC Truancy Center between mid-April and May 26, 2005 who were administered the Personal Experience Screening Questionnaire, 18% scored 25 to 52?indicating mild to moderate drug involvement. At the same time, relatively few truants report ever receiving drug abuse treatment services (3%-based on 2003-2004 truancy program data). Implementing and evaluating brief interventions, designed to address their drug abuse and their relationships with their parents/guardians, are needed to reduce their risk of moving into more serious patterns of drug use and associated troubled behavior-including justice system involvement. We propose to assess the efficacy of an existing brief intervention by conducting a four year, clinical controlled trial involving truant youths (N = 300) entering the Tampa JAC truancy program and their parents/guardians. We will randomly assign truant youth to one of three conditions: brief intervention-youth only (BI-Y), brief intervention-youth and parent (BI-YP), or standard services protocol (STS). Specific Aims are: AIM 1: Test the efficacy of BI-Y and BI-YP on post- program drug use and related behaviors for truant youth. AIM 2: Test the relative effects of parental involvement in the Bl on post-treatment drug use. AIM 3: Identify youth and parent factors that are associated with significant post-program improvement (reductions in drug use, delinquent behavior and improvement in school performance). We hypothesize that both Bl conditions will show greater reductions in drug use and improved school performance compared with the control group, and the BI-YP group will show greater improvement on these measures than the BI-Y group.